$OpenBSD: patch-include_misc_functional_h,v 1.1 2017/05/06 02:51:13 espie Exp $
those are standard in C++11

Index: include/misc/functional.h
--- include/misc/functional.h.orig
+++ include/misc/functional.h
@@ -1,6 +1,7 @@
 #ifndef FUNCTIONAL_INCLUDED
 #define FUNCTIONAL_INCLUDED
 
+#if __cplusplus < 201103L
 #include <tr1/functional>
 
 namespace std {
@@ -11,5 +12,8 @@ namespace std {
 		using namespace std::tr1::placeholders;
 	}
 }
+#else
+#include <functional>
+#endif
 
 #endif //FUNCTIONAL_INCLUDED
